Archive cool NixOS
pot-hole/missing stair: single-user Nix installs use
/run/user/$uid which is often a tiny tmpfs:
I just performed a single-user install of Nix in Fedora 30 using the install script. Tried building something that extracts a big source file and got "No space left on device" errors even though there is plenty of space available on the root filesystem. It turns out that Nix is putting build directories into /run/user/<pid>, which is a tmpfs with only a few hundred MB available in my case.
I could work around this by setting TMPDIR=/tmp, but I think this behavior is inappropriate as a default.